Alternate electronic and molecular structural formulations for oxidized iron porphyrin vinylidene-carbene complexes

Abstract

Oxidation of iron porphyrin vinylidene complexes yields products previously formulated as having an important iron(IV) porphyrin π-cation radical resonance form. Reconsideration of literature results and analogous cobalt porphyrin reactions leads to the conclusion that pyrrole nitrogen alkylation occurs and that the likely electronic structure is that of an intermediate-spin (S = $\text{3}\text{2}$) iron(III) porphyrin.